infra
/
init-wrapper
1
0
Fork 0
Code Packages Projects Releases Activity

할당자 교체

This commit is contained in:
Sangbum Kim 2025-05-19 05:42:01 +09:00
parent 2e653268c8
commit 99c1df2a99
3 changed files with 7 additions and 103 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
Cargo.toml
View File

@ -9,6 +9,7 @@ edition = "2018"
libc = { version = "0.2", default-features = false }
libc-print = "0.1.23"
errno = { version = "*", default-features = false }
static-alloc = "0.2.5"
[profile.dev]
# This isn't required for development builds, but makes development

12
Dockerfile
View File

@ -25,15 +25,11 @@ RUN set -x && \
objcopy -R .eh_frame -R .got.plt target/release/init-wrapper target/release/init-wrapper && \
ls -alh target/release/init-wrapper && \
readelf -W -S ./target/release/init-wrapper
# && \
# ./target/release/init-wrapper
# ldd target/release/init-wrapper && \
# && \
# ldd target/release/init-wrapper
RUN --mount=type=bind,rw,source=.,target=/host \
cp -avf target/release/init-wrapper /host/init-wrapper && \
./target/release/init-wrapper
RUN --mount=type=bind,rw,source=.,target=/host \
cp -avf target/release/init-wrapper /host/init-wrapper
# cp -avf target/release/init-wrapper /host/init-wrapper && \
# ./target/release/init-wrapper
FROM scratch

97
src/mem.rs
View File

@ -1,96 +1,3 @@
use core::alloc::{GlobalAlloc, Layout};
use core::{cmp, mem, ptr};
use libc::{c_void, calloc, free, malloc, posix_memalign, realloc};
const MIN_ALIGN: usize = 16;
/// The global allocator type.
#[derive(Default)]
pub struct Allocator;
impl Allocator {}
unsafe impl GlobalAlloc for Allocator {
#[inline]
unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
// jemalloc provides alignment less than MIN_ALIGN for small allocations.
// So only rely on MIN_ALIGN if size >= align.
// Also see <https://github.com/rust-lang/rust/issues/45955> and
// <https://github.com/rust-lang/rust/issues/62251#issuecomment-507580914>.
if layout.align() <= MIN_ALIGN && layout.align() <= layout.size() {
malloc(layout.size()) as *mut u8
} else {
#[cfg(target_os = "macos")]
{
if layout.align() > (1 << 31) {
return ptr::null_mut();
}
}
aligned_malloc(&layout)
}
}
#[inline]
unsafe fn alloc_zeroed(&self, layout: Layout) -> *mut u8 {
// See the comment above in `alloc` for why this check looks the way it does.
if layout.align() <= MIN_ALIGN && layout.align() <= layout.size() {
calloc(layout.size(), 1) as *mut u8
} else {
let ptr = self.alloc(layout);
if !ptr.is_null() {
ptr::write_bytes(ptr, 0, layout.size());
}
ptr
}
}
#[inline]
unsafe fn dealloc(&self, ptr: *mut u8, _layout: Layout) {
free(ptr as *mut c_void)
}
#[inline]
unsafe fn realloc(&self, ptr: *mut u8, layout: Layout, new_size: usize) -> *mut u8 {
if layout.align() <= MIN_ALIGN && layout.align() <= new_size {
realloc(ptr as *mut c_void, new_size) as *mut u8
} else {
realloc_fallback(self, ptr, layout, new_size)
}
}
}
/// The static global allocator.
use static_alloc::Bump;
#[global_allocator]
static GLOBAL_ALLOCATOR: Allocator = Allocator;
#[inline]
unsafe fn aligned_malloc(layout: &Layout) -> *mut u8 {
let mut out = ptr::null_mut();
// posix_memalign requires that the alignment be a multiple of `sizeof(void*)`.
// Since these are all powers of 2, we can just use max.
let align = layout.align().max(mem::size_of::<usize>());
let ret = posix_memalign(&mut out, align, layout.size());
if ret != 0 {
ptr::null_mut()
} else {
out as *mut u8
}
}
#[inline]
unsafe fn realloc_fallback(
allocator: &Allocator,
ptr: *mut u8,
old_layout: Layout,
new_size: usize,
) -> *mut u8 {
// Docs for GlobalAlloc::realloc require this to be valid:
let new_layout = Layout::from_size_align_unchecked(new_size, old_layout.align());
let new_ptr = allocator.alloc(new_layout);
if !new_ptr.is_null() {
let size = cmp::min(old_layout.size(), new_size);
ptr::copy_nonoverlapping(ptr, new_ptr, size);
allocator.dealloc(ptr, old_layout);
}
new_ptr
}
static GLOBAL_ALLOCATOR: Bump<[u8; 1 << 16]> = Bump::uninit();